1. Field of the Invention
The invention relates to locks such as dead-bolt locks which are mounted within a door.
The invention specifically relates to the manner in which the rosette which defines the keyway in a door lock and provides secure access thereto is coupled to the body of the door lock.
In particular, the invention provides the means for securing a rosette to a door lock cylinder without the use of external screw fasteners.
2. Prior Art
Door locks are generally provided with a central bore to accommodate the keyway and the locking mechanism. A conical flange, frequently referred to as a rosette, defines the keyway bore and provides secure access thereto. The rosette is frequently screw-threaded to the body of the lock or the lock cylinder. Means are then provided to make it difficult for an intruder to disengage the threaded coupling securing the rosette to the lock housing. To this end, a set screw is frequently driven in an interferring manner against the threaded couplings which engage the rosette to the lock body. Such attempts to secure the rosette to the lock body achieve marginal success at best. An intruder is frequently able to overcome the restraint applied to the threaded couplings and successfully remove the rosette and thus gain access to the inner workings of the lock.
It is therefore an objective of the invention to provide means for securing a rosette to a lock body by other than a threaded coupling.
It is a further object of the invention to provide a mechanical interference stop coupling for mounting a rosette to the body of a lock.
It is another object of the invention to provide a mechanical coupling of the rosette to a lock body in combination with mechanical means for locking the rosette into position and inhibiting the decoupling of the rosette from the lock body.